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APR Catback Exhaust System - S4 / S5 (B9)
APR Catback Exhaust System - S4 / S5 (B9)
APR Catback Exhaust System - S4 / S5 (B9)
APR Catback Exhaust System - S4 / S5 (B9)
APR Catback Exhaust System - S4 / S5 (B9)
  • SKU: CBK0012
  • Availability: In stock Usually ships within 5-7 Days Special Order 4-6 Weeks

APR Catback Exhaust System - S4 / S5 (B9)

$2,287.00 $2,573.00
  • Brand: APR
  • UPC:

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DESCRIPTION

Introducing the APR Catback Exhaust System for the Audi B9 S4 and S5

The APR Catback Exhaust System for the Audi B9 S4 and S5 is a complete, high-performance exhaust solution that runs the entire length of the vehicle from the catalyst back. Inspired by the larger center-pipe design of the higher-output RS4 and RS5 models, this system is engineered to boost performance, elevate sound, and enhance aesthetics with customizable exhaust tips that are sure to make a statement. Crafted from premium materials and built with advanced manufacturing techniques, this system is designed to withstand harsh conditions and deliver lasting performance. Expect a bold, aggressive growl at wide-open throttle, along with an impressive gain of 10 horsepower and 12 FT-LBS of torque to all four wheels! Unmatched Design and Precision Engineering

Unlike anything currently available, the APR system includes downpipes extending to the factory catalyst in the upper engine bay, making this a true full-system upgrade. We’ve minimized restrictions with smooth transitions, oversized piping, and straight-through mufflers and resonators. Constructed from mandrel-bent T304 stainless steel with a brushed finish and TIG welding throughout, this exhaust system is as durable as it is striking. Installation is hassle-free, thanks to precision-fit brackets, OEM-style slip clamps, and an included upgraded tunnel brace to accommodate the oversized piping. Inspired by RS Performance

Like the RS4 and RS5, this system features a reengineered exhaust routing design. It utilizes dual 2.5” (63.5mm) downpipes to dual 2.75” (70mm) midpipes pipes merging through a cast Y-junction into a massive 3.5” (91mm) midpipe, replacing the restrictive factory dual-pipe setup. The integrated Helmholtz resonator minimizes drone through a straight-through design with a sound-canceling port, ensuring no compromise in exhaust flow.

The system splits again via another cast Y into two rear, valve-controlled mufflers with sound absorption technology. These valves are fully integrated with the OEM control system, adjusting automatically to enhance sound during aggressive driving while maintaining a quieter profile during cruising. Finally, exhaust gases exit through dual cast Y-junctions into a quad 2.5” (63.5mm) system, terminating in 3.5” (91mm) lightweight, single-walled motorsport-style tips. The tips feature a polished stainless steel finish and a subtle APR logo for a refined touch. Experience the APR Difference

Designed for enthusiasts seeking the perfect balance of power, sound, style, and quality, the APR Catback Exhaust System for the Audi B9 S4 and S5 is a testament to engineering excellence. With its performance-driven design and durable construction, this system not only transforms your driving experience but also ensures years of reliable performance.

APR Catback Exhaust System - S4 / S5 (B9)

Features

  • Complete catalyst-back system including downpipes, extending from the factory catalyst back.
  • Performance gains of 10 HP and 12 FT-LBS of torque delivered to all four wheels.
  • Premium T304 stainless steel construction with TIG welding for strength and durability.
  • Optimized flow through dual 2.5” downpipes, 2.75” midpipes, and a 3.5” midpipe.
  • Mandrel-bent brushed piping paired with electropolished cast splitters for a refined finish.
  • Precision brackets and slip clamps ensure accurate alignment and hassle-free installation.
  • Includes an upgraded tunnel brace to accommodate the larger piping.
  • Integrated Helmholtz resonator minimizes drone and enhances sound quality.
  • Valve-controlled rear mufflers dynamically adjust sound based on driving style.
  • Removable quad 3.5” motorsport-style polished tips with APR logo; optional styles available.
  • Smooth transitions and straight-through components maximize performance by reducing restrictions.
  • Strikes the perfect balance of power, sound, style, and quality for enthusiasts.
  • Fully emissions compliant for worry-free operation.

Tech specs

Brackets Precise
Clamping Type Slip Clamp
Clamps Included Yes
Exhaust Tip Color Polished
Exhaust Tip Diameter 3.5 IN
Exhaust Tip Finish Carbon Fiber with Brushed Inlay
Exhaust Tip Quantity 4
Exhaust Tip Removable Yes
Finish Brushed
Grade Type Performance
Hangers Included Yes
Main Piping Diameter 2.50 IN
Material T304 Stainless Steel
Muffler Finish Brushed
Muffler Quantity 2
Muffler Type Helmholtz
Pipe Bend Type Mandrel
Pipe Material T304 Stainless Steel
System Type Catback
Tail Pipe Outlet Outside Diameter 2.5 IN
Tube Connection Butt Joint
Valve Included Yes
Valve Type OEM
Welding TIG

Watch

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Install

Installation guide (PDF)

VEHICLE LIST
DIMENSIONS
DOCUMENTS
AVAILABILITY

Please read before ordering. Eurosport Performance does not carry live inventory on this site. Most products are ordered for you directly from the manufacturer or our suppliers, and we follow their lead times. Placing an order confirms you have read and accepted the availability terms below.

In stock
Ships within 24 to 48 hours
Products marked in stock are on our shelves in Montreal and leave within one to two business days.
Ordered for you
Most orders ship in 5 to 7 business days
Everything else is ordered from the manufacturer or supplier when you order. Delays can occur; if they do, we contact you.
Supplier lead times apply
If a product is not listed as in stock here and is on backorder at the manufacturer, it will most likely be on backorder for us too. We will tell you as soon as we know.
We keep you informed
You receive a confirmation when the order is placed, a notice if a delay comes up, and tracking the moment it ships.
Frequently asked questions
Is this product in stock right now?

Only products explicitly marked in stock are on our shelves. For everything else, the fastest way to know the current lead time is to ask us before you order; we check with the supplier and reply with a date.

Why does my order say "confirmed" but has not shipped?

Confirmed means we have placed the order with the manufacturer or supplier on your behalf. Shipping follows once the part reaches us or ships directly to you, usually within 5 to 7 business days for products that are available at the source.

What happens if the part is on backorder?

We tell you as soon as the supplier confirms it, with the expected date when they give one. You can keep the order open, switch to an alternative we suggest, or cancel for a full refund before the part ships.

Can I cancel if it is taking too long?

Yes. Any order that has not shipped can be cancelled by contacting us, and the refund goes back to your original payment method. Please contact us rather than opening a dispute with your bank: a cancellation takes us minutes, a chargeback takes weeks and freezes the refund in the meantime.

Do you ship directly from the manufacturer?

Sometimes. Larger or special-order items can ship to you directly from the supplier to save days in transit. You still receive tracking from us either way.

Where do my parts ship from, and are there duties?

Orders ship from Montreal or directly from our suppliers. For Canadian addresses the price you pay is the price, with no import or duty fees added on delivery. See our shipping policy for details.

How will I know when it ships?

You get an email with the tracking number the moment the label is created, and you can follow the order in your account on the site or in the SPECD app.

Want a lead time before you order? Email us or use the contact page with the product name and your vehicle, and we will confirm availability with the supplier.

WARRANTY

Products are warrantied by their manufacturer. Eurosport Performance is an authorized reseller: every part we sell is covered by the manufacturer's own warranty, with its own terms and duration. Claims go through us, so you deal with Eurosport Performance rather than a form on the brand's site, but whether a claim is accepted is the manufacturer's decision.

Manufacturer terms apply
Duration and coverage are set by the brand and differ from one to the next: some cover one year, some a lifetime, some only the original purchaser. The brand's warranty page is the reference; ask us if you cannot find it.
We file the claim for you
Contact us with your order number, photos and a description of the issue. We open the claim with the manufacturer, follow it up, and arrange the repair, replacement or credit they approve. The manufacturer decides whether the claim is accepted.
Fitment guarantee: North America only
We guarantee fitment for vehicles sold in the North American market. Vehicles from other markets are out of scope; specifications differ, and it is the customer's responsibility to confirm compatibility before ordering.
No warranty on tuning files
ECU and TCU tunes and other software files are sold without warranty and are not returnable once delivered or flashed. Tuning can affect your vehicle's factory warranty; please read the brand's terms before purchasing.
Proof of purchase
Your Eurosport Performance order is the proof of purchase every manufacturer asks for. Keep the order confirmation; it is also in your account on the site and in the SPECD app.
What is usually not covered
Damage from improper installation, modification, abuse, racing or an incorrect application for the vehicle, and normal wear items such as pads, clutch discs and filters. Shipping and labour are covered only when the manufacturer's terms say so.
Frequently asked questions
How long is the warranty on this product?

It is the manufacturer's warranty for that product. Where the brand publishes it, we note it in the description; otherwise contact us before ordering and we will confirm the exact terms with them.

A part failed. What do I do?

Stop using it if it is a safety-related part, then contact us with your order number, clear photos, and when and how the issue appeared. Do not return anything until we confirm the claim; manufacturers often require an inspection or an authorization number first.

Who decides if my claim is accepted?

The manufacturer. We prepare and submit the claim, provide the proof of purchase and push for a fair outcome, but acceptance, replacement or credit is their call under their terms. We pass their decision on to you as soon as we have it.

How long does a claim take?

It depends on the manufacturer. Simple cases are approved in days; claims that need the part inspected can take a few weeks. We keep you updated at each step and push when it drags.

Is there a warranty on ECU or TCU tunes?

No. Tuning files are software; once delivered or flashed they cannot be returned, and they carry no warranty from Eurosport Performance or, in most cases, from the tuner. Support for the tune itself (revisions, flashing questions) comes from the tuning brand under its own terms.

My car is from outside North America. Is fitment guaranteed?

No. Our fitment guarantee covers vehicles sold in the North American market only. European, Japanese and other market vehicles can differ in engines, electronics and dimensions, and a part listed for the North American model is not guaranteed to fit. If you order for one of these vehicles, confirming compatibility is your responsibility, and fitment issues on such vehicles are not covered by returns or warranty.

Is installation covered?

Labour is not covered unless the manufacturer's terms specifically include it. Having the part installed by a qualified shop protects your claim: improper installation is the most common reason a manufacturer declines.

Is a warranty issue the same as a return?

No. Returns cover unused parts you no longer want, under our refund policy. Warranty covers a part that fails in use, under the manufacturer's terms. If you are unsure which applies, contact us and we will point you to the right one; please do not open a bank dispute, as it pauses both processes.

Questions about coverage before you buy? Email us with the product and your vehicle and we will confirm the manufacturer's terms.

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